Added screenshot thumbnail
Added additional utils methods...

- a method showing a Swing-based information dialog, for when SWT failed
to initialise
- a method to copy RGB objects
Marginally optimized basic controller movement
Modified dialogs to remember prev selection...

...fixed tree columns being resizable beyond the tree's own width
removed the horizontal bar from the trees to prevent it from flickering
when the dialog window is resized
Added a popup about wrong version of the editor
Added default colors for Views, decoupled room...

...and system drawing -- systems are drawn on a separate layer above
rooms,
Added crew modification, removed the ampersand...

...since it doesn't display correctly on some systems,
Changed StringBuilders to String concatenation, since Java's compiler
optimizes Strings that are known at compile time
Added tooltips, added more windows to focus check
Fixed systems not being redrawn correctly, misc
Update readme_changelog.txt